2. Chapter 3.3 Carbohydrates

3. So what’s all this talk about carbs? Atkin’s diet & South Beach diet reduces carbohydrate intake. That ’ s no pyramid! What the heck?

4. Carbohydrates  Carbohydrates are composed of C, H, O carbo - hydr - ate CH 2 O (CH 2 O) x C 6 H 12 O 6  Function:  energy u energy storage  raw materials u structural materials  Monomer: sugars  ex: sugars & starches

5. Sugars  Most names for sugars end in -ose  Classified by number of carbons  hexose (glucose)  pentose (fructose, ribose)  triose (glyceraldehyde)

6. What functional groups? carbonyl ketone aldehyde hydroxyl

7. Sugar Structure  5C & 6C sugars form rings in aqueous solutions  in cells! Carbons are numbered!

8. Numbered Carbons C CC C C C 1' 2'3' 4' 5' 6' O

9. Simple & Complex Sugars  Monosaccharides  simple 1 monomer sugars  glucose  Disaccharides  2 monomers  sucrose  Polysaccharides  large polymers  starch

10. Building Sugars  Dehydration synthesis | glucose | glucose glycosidic linkage monosaccharidesdisaccharide | maltose

11. Building Sugars  Dehydration synthesis monosaccharidesdisaccharide | fructose | glucose glycosidic linkage | sucrose structural isomers

12. Polysaccharides  Polymers of sugars  costs little energy to build  easily reversible = release energy  Function:  energy storage  starch (plants)  glycogen (animals)  building materials = structure  cellulose (plants)  chitin (arthropods & fungi)

13. Branched vs. Linear Polysaccharides

14. Polysaccharide Diversity  Molecular structure determines function  Isomers of glucose  How does structure influence function…

15. Digesting Starch vs. Cellulose

16. Cellulose  Most abundant organic compound on Earth

17. Glycemic Index  Ranking of carbohydrates based on their immediate effect on blood glucose (blood sugar) levels  Carbohydrate foods that breakdown quickly during digestion have the highest glycemic indices. Their blood sugar response is fast & high.

18. Glycemic Index  Which food will get into your blood more quickly?  apple  rice cakes  corn flakes  bagel  peanut M&M

19. Glycemic Index  Which food will get into your blood more quickly?  apple36  rice cakes82  corn flakes84  bagel72  peanut M&M33 Questions anyone?